Uses different material

Walter W. Frogatt, The Insect Book, Australian Nature Series, Sidney, Consolidated Press, 1943, p. 34-35.

« Caddis worms » have soft skins, and each makes a long cylindrical silken bag, open at both ends, as a case for it when floating about on the surface of the pond, or when crawling over the mud at the bottom. Each species makes a different sort of house and uses different material, tiny stones, bits of stick or leaf, or little shells. These material are fastened together with a silky webbing from the body.